What happened outside Parliament?

Members of the emergency services work to help vicitms on Westminster Bridge, alongside the Houses of Parliament in central London on March 22, 2017, during an emergency incident (Picture: Getty)

A massive police investigation is under way after a terror attack in central London.

Here's everything we know so far about the Westminster attack:

Six people have died - a police officer, the attacker, a woman named as Aysha Frade, 43, US tourist Kurt Cochran, 75-year-old Leslie Rhodes and Romanian tourist Andreea Cristea who died 15 days after being pulled from the Thames.

The officer was Pc Keith Palmer, a 48-year-old husband and father with 15 years of police service.